Facet grinding attachment



2 Shgets-Sheet 1.-

Filed July 26, 1941.

Ficni FiGB O m 3m M .l 5 3 m m 0 V T 2 Fflmut mmw A s w w W 4. l 6 K A Y 9 m 6/ G%% w P {H y a 3 flu Patented Sept. 29, 1942 UNlT ED STATES PATENT OFF-ICE FACET GRINDING ATTAGH-MENT Harry Kousin, New York, N. Y.

ApplicationJuiy 26, 1941, Serial No. 404,130

"9 Claims.

My invention relates to facet grinding attachments and has particular reference to attachments or devices for grinding facets bya grinding wheel.

The object of my invention isto providemeans accompanying specification and drawings, in

which:

Fig. 1 is a perspective view of my attachment employing a motor driven grinding wheel;

Fig. 2 is a sectional elevation of a work holding post;

Fig. 3 is a top plan View of the post;

Fig. 4 is an elevational view of a modified post; Figs. 5 and 6 are bottom views of different posts;

Figs. 7 and 8 are plan views of adapters for the posts;

adapter l3 may be placed between the postand the ring to fit different sizes of the rings, the adapterxbeing also split or slotted in'oneor more places, the slots extending partway into the adapter from different ends.

The height of the adapter can be adjusted by liners l4 placed between the rails.

The post with the ring on top is moved by hand between the rails against the Wheel 3 for grinding a facet. Upon completion of one facet, the post is moved back and removed from the rails. For grinding the next facet, the post is turned at an angle corresponding to theang-le between the facets and again placed between the rails. The operation is continued until all the facets are finished.

Figs. 9 and 10 are views of a modified device;

Fig. 11 is an elevational view of a modified device;

Fig. 12 is a plan view of the post supporting table;

Fig. 13 is a detail view of the post; and

Figs. 14 and 15 are views of a modified device.

My facet grinding attachment consists of a base I supporting at one end an electric motor 2 having a grinding wheel 3 on its shaft. Rails 4 are mounted on the other end of the base 1, extending at right angles to the face of the grinding wheel. The rails are used for guiding a post 5 having a polygonal base 6, preferably with an even number of facets, so that the distance between the opposite facets corresponds to the distance between the rails.

The post is hollow inside, its upper portion being split at 1, so that it can be expanded by a cone 8 engaging a tapering or conical upper opening in the post. The cone is threaded inside for a screw 9 having a head !9 resting against a shoulder H in the base of the post. By turning the screw 9, the cone is forced into the tapering opening, expanding the upper end of the post and clamping any annular object placed thereon such as a ring l2. A tubular In order to limit the depth of the facets, a stop is provided for the post, such as is shown in Fig. 1, and consisting of a bar 15 placed on top of the rails and fastened with thumb screws IS. The bar has elongated holes IT for the screws, so that it can be adjusted for a position corresponding to the desireddept-h of facets on a particular ring.

It should be noted that the grinding wheel 3 may be rotatively supported in any suitable manner and driven .by any suitable source of power.

Several posts may be provided having bases of different shapes, such as octagonal 18, Fig. 5, decagonal l9, Fig. 6, etc.

Instead of having several posts for different number of. facets, it is possible to have ,a single post with a hexagonal base, for instance, and a plurality of adapters such as 21?, Fig. '7, 2|,Fig.

.8, etc., the adapters having difierent number of facets, but all fittingbetween the rails, the dis- 'The post.22 .has a shoulder 23 at the base-fitting under corresponding recesses 24 in rails '25. The post is .thus dovetailed between the rails and tends to retain its vertical position, so that it cannot be tilted in pressing against the wheel 3.

The guiding member or rails 4 can be'mounted on a pin 26 (Figs. 1 and'9) fitted-in a slot .2"! in the base I, so that the rails can be turned at right angles to the base as shown in dotted lines in Fig. l for grinding objects against the edge of the wheel 3. The slot 2'! is sufficiently long, as shown in Fig. 9 so that the rails can be moved out and raised on the threaded pin 26 for supporting small articles at an elevation against a tool 28 clamped in a chuck 28 at the end of the motor spindle 30. The tool may be a drill, reamer, milling cutter, etc. It can be also used for drilling holes in a ring mounted on the post 5 with the rails in the lowered position.

The rails 4 may be mounted on a platform 3| pivoted at 32 to the upper end of the threaded post 26,- so that the platform with the rails can be tilted as shown in Fig. for grinding angular facets on rings and similar objects. A second post 33 is provided for supporting the outer portion of the rail platform, the post 33 being also pivoted at 34.

It may be provided with notches 35 for locking it in a desired position, the notch at a desired height being engaged by a sliding key 36. The post 33 is disconnected from the platform when the latter is placed at right angles to the wheel.

The motor 2 is provided with a controller or rheostat 31 having a handle 38' for changing speeds.

A modified device is shown in Fig. 11. The table 39 has a hole for a rod 40 attached to a base plate 4|, so that the latter can be turned at a desired angle to the wheel 3. The plate can also be raised, the rod being clamped in a raised position by a screw 42 threaded in a tubular extension 43 under the table. An upper plate 44 is hinged at 45 to the base plate and has rails 46 for a sliding block 41. A bar 48 is pivotally connected at 49 to the upper plate and slides in a slot 50 in an extension 5|, a screw 52 being provided for clamping the bar when the upper plate is inclined. The block 41 has a round opening for a post 53. The latter has two peripheral grooves 54, 54' with equally spaced holes or depressions 55, 55'. The latter are engaged by aball 56 under pressure of a spring 51. The upper portion of the post may be provided with sixteen holes, for instance, while the lower may have twelve.

The upper surface of the block 41 has divisions 58 corresponding to various positions of the post.

For using the lower row of holes 55, the block It is understood that my facet grinding attachment may be further modified without departing from the spirit of the invention, as set forth in the appended claims.

I claim as my invention:

1. A facet grinding attachment comprising a base, parallel guiding rails on the base, a grinding wheel rotatively supported above the base with its plane at right angles to the rails, a post having a polygonal base with parallel opposite sides adapted to be slidably moved between the rails, means on the post for holding an object to be ground by the wheel, and liners on the base between the rails for adjusting the height of the post.

2. A facet grinding attachment comprising a base, parallel guiding rails on the base, a grinding wheel rotatively supported above the base with its plane at right angles to the rails, a post having a polygonal base adapted to be slidably moved between the rails, means on the post to support an object to be ground by the wheel, and means at the rails to limit the movement of the post.

3. A facet grinding attachment comprising a base, parallel guiding rails on the base, a grinding wheel rotatively supported above the base with its plane at right angles to the rails, a post having a polygonal base adapted to support an object to be ground, and an adapter having a recess for the polygonal base of the post and having an outer polygonal base adapted to be slidably moved between the rails.

4. A facet grinding attachment comprising a base, a, grinding wheel rotatively supported on the base, guiding rails in front of the wheel, a block slidably supported between the rails, a post adapted to support an object to be ground having a cylindrical base, the block having a cylindrical opening for the base of the post, the base of the post having at the periphery a plurality 41 is reversed, the under side having divisions corresponding to the lower row of the holes 55. The post can be used for grinding various objects, including precious stones 60, which may be cemented to the top of the post 59, Fig. 13.

With sixteen holes in the post, it is possible to grind sixteen facets, or, skipping every other hole, eight facets, etc. The post can be made, of course, with any desired number of holes for grinding a corresponding number of facets.

Another modification is shown in Figs. 14 and 15. ihe block 41 slides between rails Bl on a cross-bar 62. The latter has lugs 63 sliding between the rails 46. The cross-bar can be moved against the wheel 3 or held in any desired position by a clamping screw 64 threaded in a lug 65. The block 41 can be then moved back and forth across the face of the wheel 3 for obtaining a smooth ground facet on the ring 12.

In order to obtain uniform depth of grinding for all facets, the ring is held at a fixed distance from the wheel 3 by clamping the cross-bar in a desired position, and the wheel 3 is moved against the ring by turning an adjusting micrometric screw 66, Fig. 11. The screw moves the upper arm of a lever 81 pivoted at 68 on top of the motor 2. The lower arm of the lever has a sharp point 69 bearing against the end 10 of the shaft 1| of the motor. A spring 12 urges the shaft to the left, pressing it against the point 69. Divisions 12 on the head 13 of the screw indicate the position of the screw as against a of equally spaced holes, and means on theblock to yieldably engage the'holes on the post.

5. A facet grinding attachment comprising a base, a grinding wheel rotatively supported on the base, guiding rails in front of the wheel, a block slidably supported between the rails, a post adapted to support an object to be ground having a cylindrical base, the block having a cylindrical opening for the base of the post, the base of the post having at the periphery a plurality of rows of equally spaced holes, means on the block in the opening to yieldably engage the holes, and means to render one ofthe rows operative.

6. A facet grinding device comprising a base, a grinding wheel rotatively supported on the base, a platform on the base, a rod attached to the platform extending downward through an opening in the base, a second platform hingedly supported at the inner end of the first platform adapted to be raised into an inclined position in relation to the wheel, means to retain the second platform in the inclined position, the rod with the platform being adapted to be raised, means to retain the rod in the raised position, rails on the second platform, a work-supporting post, means to slidably support the post between the rails, the post being adapted to be rotated on its vertical axis, and yieldable means-tolretain the post in equally spaced fixed positions in relation to'the wheel. a

'1. A facet grinding'attachment comprising a base, a grinding wheelrotatively supported on the base, guiding rails in front of the wheel, a cross-bar movably supported on the rails, guiding rails on the cross-bar extending at right angles to the axis of the wheel, a block slidably supported on the cross-bar rails, a post on the block, and means to support work on the post, the cross-bar being adapted to be moved toward the wheel, for grinding the work.

8. A facet grinding attachment comprising a base, a grinding wheel rotatively supported on the base, guiding rails in front of the wheel, a cross-bar movably supported on the rails, guiding rails on the cross-bar extending at right angles to the axis of the wheel, a block slidably supported on the cross-bar rails, a post on the block, means to support work on the post, the cross-bar being adapted to be moved toward the wheel for grinding the work, and means to releasably hold the cross-bar in a desired position.

9. A facet grinding attachment comprising a base, a motor on the base having a shaft adapted to be moved in axial direction, a, grinding wheel at one end of the shaft, means to adjustably support a work in front of the wheel, a micrometric screw on the motor, means to adjust the axial position of the shaft by the screw, and a spring urging the shaft against the screw.

HARRY KOUSIN. 

